Evaluation of osseous response to bioglass/dextran composite in induced mandibular defects: an experimental study

This experimental study was made to evaluate the osteogenic potential of Bioglass/Dextran composite clinically, radiographically and histologically in induced mandibular bone defects in 12 mongrel dogs and suitability of this material to the ridge augmentation procedures. In the right mandibular side, first molar was removed followed by localized alveolectomy then the site was compressed with the composite graft while in the left side, a rectangular defect was surgically induced with dimensions 20 x l0x 5 mm just below the inferior alveolar canal then compressed with the graft material. Both grafted defects were compared with the control animals along intervals 3, 6 and 12 weeks postoperative periods clinically, radiographically, histologically and histomorphometrically. the current study proved that this composite is bioactive, has high osteogenic potential and could be used effectively in large osseous defects without any adverse inflammatory, allergic or cytotoxic reactions. In addition, this composite could be used in alveolar ridge augmentation procedures as it caused a statistically significant increase in rate and density of bone formation in these defects compared to the control animals. Bioglass/Dextran composite is an effective osteoconductive and osteostimulatory graft material that could be used in large osseous defects and in ridge augmentation procedures especially with the use of barrier membrane

Dentin and enamel shear bond strengths using fluorinated bis-EMA resins

Statement of problem. It is well accepted that bond strength is affected by the extent of resin infiltration into the exposed collagen network. However, failure often occurs

Purpose: The purpose of this study was to examine the bonding of commercial and an experimental bis-EMA composite resin with fluorinated TEGDMA [F-T] to enamel and dentin using experimental bonding resins, containing F-T

Materials and Methods: Light-curable, filled and unfilled bonding resins were made with F-T concentrations of 0, 17, 24, and 30 wt.%. Silanized barium silicate glass was used for the filled resins at 48 wt. %. Enamel and dentin, mounted in epoxy resin disc were 600 grit finished metallographicallly yielding a flat surface with a smear layer. OptiBond Solo Plus and All-Bond 2 etchants and primers were used with the filled and unfilled experimental bonding resins to bond commercial and experimental composite resin cylinders 5 mm diameter and 2.5 heights to dental tissues. Five specimens for each group were made and stored at 37 [degree sign] C for 24 hour. These were tested in shear mode at 0.5 mm/min in a universal testing machine. Bond strengths to enamel and dentin were analyzed separately using 3-way ANOVA and Ryan-Einot-Gabriel-Welsch Range Test [REGWQ] with filler, F-T concentration, and composite resin type as dependent factors

Result: Filler content was statistically significant [p<0.05]; all other factors were not significant. With dentin bonding, many interactions were statistically significant, only the type of composite resin and the presence of filler were not significant

Conclusion: The data suggest enamel bonding is fairly consistent, irrespective of the bonding resin used but dentin bonding is more sensitive to resin formulation